UPS CEO David Abney urged business leaders to push Congress to ratify the controversial Trans-Pacific Partnership trade deal, arguing that small businesses interested in reaching new international markets face too much red tape under the status quo.

"The unsung hero of this deal is going to be the small and mid-sized enterprises," Abney said. UPS is a longtime advocate of free trade.

Abney made the remarks during a luncheon on the Trans-Pacific Partnership hosted by the World Affairs Council of Atlanta, an event that also featured remarks by Atlanta Mayor Kasim Reed, former U.S. Sen. Saxby Chambliss and deputy U.S. trade representative Robert Holleyman.

The 12-nation free trade deal known as TPP is championed by President Barack Obama but opposed by both presidential candidates Donald Trump and Hillary Clinton.

Among those also in opposition to TPP is the Teamsters union representing UPS drivers, whose members protested outside the downtown Atlanta building where the luncheon was held Monday.

“We’re opposed to the TPP because we feel like it’s going to undermine American workers’ standard of living,” said Teamsters Local 728 political director Eric Robertson. “They need to pass real protections for working people.”

Obama is moving to push the deal forward. But it will be an uphill battle.

Reed said if the deal is not ratified during the lame duck session of Congress, it’s unlikely to happen under the next president.

Small businesses “rely on international trade rules to access overseas markets,” Reed said. TPP “will help level the playing field for workers and businesses in the U.S.,” he said.